sparqdown-graph coherence namespace
The sdgco: namespace holds the coherence-engine vocabulary — the terms a @rule block emits into a TypeDefinition's canonical RDF so the engine can check whether a document honors the type it claims to be. A rule is a subject a sdgco:Rule, linked to its type by sdgco:hasRule, carrying a sdgco:severity (the sdgco:Error, sdgco:Warning, or sdgco:Info individual), a human sdgco:description, an optional sdgco:condition guard, and a required sdgco:assertion SPARQL query.
The namespace also reserves the suppression predicates the evaluation engine reads — sdgco:suppresses and sdgco:reason — which an instance document uses to silence a named rule with a mandatory justification.
"Coherence" spans both facets the mechanism covers: is this a valid piece? (the document is well-formed and honors its type's shape) and does it fit the whole? (the piece interlocks with the existing body of knowledge). The prefix parallels how labels live at sdgl: under sdg:.
Membership in this namespace is derived by the Lexicon from the declaration above — see Namespace Definition.